Oscar Gauthier was a prominent member of the Abstraction Lyrique group, which was the European equivalent to the American Abstract Expressionists. After World War II, there was a powerful Western urge to celebrate the superiority of liberal society through its openness to free thought. This sentiment lead to the passionate expression of unconventional creativity and manifested itself in visual art in the enthusiastic embrace of abstraction. This took a variety of forms, of which the most famous is the approach of the abstract expressionist and Abstraction Lyrique artists, whose highly gestural approach was acclaimed as the ultimate expression of the individual, the uninhibited self. It is, at once, dynamic and spontaneous, whilst also poetic and meditative.

After attending the École des Beaux Arts de Paris, and also the more avant-garde Académie de la Grande Chaumière under Othon-Friesz, where he met César and Huguette Arthur-Bertrand, Gauthier’s development was interrupted by the war. Afterwards, he returned to painting and began exhibiting at the Salon des Moins de Trente Ans, starting in 1945.

He abandoned all figuration in 1948, and held his first solo exhibition in 1949 at the prestigious Galerie Colette Allendy. Here, he became acquainted with leading artists Hartung Schneider, Deyrolle, and Domela, and held two further solo exhibitions there in 1950 and 1951. From 1952 to 1958, he exhibited at the gallery of John Robert Arnaud and the young American John Franklin Koenig in the highly fashionable area of St-Germain-de-Prés. At this cutting edge gallery, he also participated in the influential series of group shows known as the "Divergences," including Nouvelle Situation, curated by R.V. Gindertael in 1954 and Affinités, curated by Michel Ragon in 1958. During this period, Gauthier’s style evolved dramatically and he began applying the pigment with the palette knife, almost sculpting the surface of the painting. The critic Michel Ragon termed this style “abstract landscapism.” In 1959, Gauthier began exhibiting at the high profile Galerie Raymonde Cazenave, which also exhibited Lanskoy and Bryen.